Utilisation d'un asservissement de fréquence pour la détermination précise des paramètres décalage et d'élargissement de la raie J: 2 → 3 d'OCS en fonction de la pression

Abstract

An original microwave-frequency monitoring to be used in microwave spectrometry, in the Ka band, has been achieved. By means of this device, the monitoring of a source frequency at three particular points in a resonance line; i.e., center frequency and both symmetrical bending points, may be allowed without any static error.This experimental device enabled us to study the half-width parameters ΔνL/p and shift parameter δν0/p of line J = 2 → 3 of OCS versus pressure. As regards ΔνL/p, our values of the half-width parameter, ΔνL/p = 6.25 ± 0.15 KHz∙m Torr−1, have been checked by the conventional direct method (1 Torr = 133.3 Pa). Although more accurate, they agree with the other published values. However, δν0/p = 0.66 ± 0.05 KHz∙m Torr−1 is in disagreement with the two values published to date (these values being contradictory).An accurate study about the eventual causes of error ensures the reliability of this value.